PARIS — Remember conspiracy theories? There was a time, not so long ago, when we used to worry about how the internet encourages the proliferation of crackpot versions of what "really happened" on 9/11 or circulated "the ultimate proof" that Moon landings were actually staged in a television studio.

Nowadays, a website hocking a conspiracy theory seems almost quaint in the face of our so-called "post-truth" society. While such outlandish ideas were once relegated to the digital fringe, we now live in a world where bogus articles (concocted by Russia, and others) systematically wind up in our Facebook feeds and risk altering international elections, and where an American president boasts that his success as a reality TV star is a prime qualification for his current job.

The very concept of "fake news," whether manufactured to muddy the waters or used as an accusation by the likes of Donald Trump to dismiss any criticism, has somehow both elevated and depleted the currency of the conspiracy theory traffickers among us. Three years after the Charlie Hebdo attacks in Paris, a new study in France shows that nearly one in five people believe that the terrorists were aided by some other participants in the planning and executing of the assault. In the report, conducted by the Fondation Jean-Jaurès and Conspiracy Watch, some 35% of those polled also say they believe that the U.S. government had some prior knowledge of the 9/11 attacks.

As reported by the French daily Le Monde, perhaps the most troubling finding of the new study is a much higher prevalence of young people who believe in sinister plots. Whereas only 2% of older respondents had doubts about the official history of the Holocaust, 8% of those aged 18-24 believe the number of deaths have been exaggerated.

Almost quaint in the face of our so-called 'post-truth' society.

Not surprisingly, the spreading of conspiracy theories is linked to growing skepticism toward mass media. The arrival of our post-truth era, as it were, presents a connection between real-time propaganda and public doubts across the annals of history. The Columbia Journalism Review recently looked back on the good, the bad and the very very ugly in 2017 among those of us in the business of informing the public. "The industry in the midst of a reckoning in which it is both pushing the story forward and turning the lens on itself," writes Pete Vernon.

So far in 2018, the big story emanating from the U.S. has been the fallout of the new Trump exposé by Michael Wolff, questioning the mental fitness of the president. Writing in The Washington Post, columnist E.J. Dionne Jr. says that the real shocker is that we are even surprised. "President Trump's unfitness for office was obvious long before he was elected. Once he moved into the White House, the destructive chaos of his administration was there for all to see. Future historians will scratch their heads to figure out why it took this particular book to break the dam of denial."

But Dionne notes that the furor over Wolff's book could have a "paradoxical" effect in pure political terms. "It could strengthen the bonds between Republican politicians and Trump at the very moment when everyone else is coming to terms with how dangerous it is to have a president who is so uninformed and unstable. In the meantime, more traditional journalists will carry on their painstaking work, piling up evidence that Trump did all he could to block a legal accounting for the methods that helped get him to the White House in the first place."

It is all a reminder of one thing that conspiracy theorists and the rest of us may be able to agree on: History is written by the winners.

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